Virtual Assembly Analysis and Simulation in an e-Design and Realization Environment

1. Virtual Assembly Analysis and Simulation in an e-Design and Realization Environment By Bart O. Nnaji, Ph. D. William Kepler Whiteford Professor and Director and Kyoung-Yun Kim, Ph. D. Research Assistant Professor NSF Center for e-Design and Realization University of Pittsburgh Pittsburgh, PA 15261, USA

2. Objective of Presentation • To show how an e-Design system can provide synergy tools for efficient implementation of the new DoD acquisition process

3. Defense Acquisition Management Framework

4. DoD New Requirements and Acquisition Process – 3170 and 5000 Regulations

5. Integrated Architecture Operational Desired function and how to achieve it Systems System to use to achieve it. How do systems interrelate? Technical What standards apply?

6. New Acquisition Process and e-Design System e-Design System Architecture Operational Systems Technical

7. NSF Center for e-Design Center Motivation • Discrete mechanical products: • $1 trillion in U.S. revenues per year • Faster and cost effective product acquisition • E.g. Automotive design cycle now 36 – 48 months: • needs to be 18 – 24 months and eventually 12 months • More than 75% of product’s acquisition costs committed at design time • Industry needs to respond quickly with cost effective high quality products • Industry can achieve this by evolving a faster, more efficient product design and realization paradigm • Internet-based design studio can significantly reduce costs • Current design collaboration requires efficient workgroup interaction. Effort should be applied to product development and not collaboration tasks (e.g., scheduling meetings, documentation, etc.).

8. Industry Technology Needs • New paradigm in design of engineered products: systems approach • Interoperability among heterogeneous systems • Customer-oriented and supplier communication • Collaboration among all stakeholders • Remote and distributed design via Internet “online collaboration” • Design information/knowledge sharing among all collaborators • From concept to form • Direct constraint imposition • Multidisciplinary constraints • Scalable, flexible and efficient platform • Virtual product prototyping with Physical laws realization

9. Implementation of New Acquisition Process uses Global Information Grid (GIG) Global Information Grid (GIG) e-Design Service Architecture GIG supports DoD missions with IT for national security, joint operations, etc. GIG shall be planned, resourced, acquired, following DoD 5000 regulations E-Design system uses Internet-based service-oriented architecture for design realization of products and systems GIG assets shall be interoperable, following approved requirements, and compliant with operational system and technical views GIG shall be based on a common, or enterprise-level, communications and computing architecture, etc. GIG plans, architectures, designs, hardware shall support applicable levels to ensure security, management, etc.

10. Service-oriented Product Design and Realization and System Architecture • Service is defined as a process that provides a functional use for a person, an application program, or another service in the system. • Compatibility • Portability • Scalability • Extensibility • Interoperability

11. Pegasus Service Management Service Security Service Security Service Providers Service Publication AOT Service Specification Service Update Gateway Service FEM Service Protocol Simulator Service Brokerage Service Lookup Virtual Prototyping Tools Service Linkage & Reference Service Data Source Multi-kernel Agent Other Service Providers Security Access Control Service Planning & Scheduling Directory & Verification Service Service Meta-Protocol Internet Enterprise A Enterprise B Data Security Service Security Data Security Service Security FIPER Technology FIPER Technology Functionality-based Conceptual Engine Service Specification Functionality-based Conceptual Engine Service Specification Resident Design Tools Resident Design Tools Service Protocol Service Protocol Service Linkage & Reference Service Linkage & Reference Constraint Manager Client Data Source Constraint Manager Client Data Source Service Data Source Service Data Source e-Design Information Infrastructure

12. Illustration of Integrated Use of e-Design • New paradigm in design of engineered products: systems approach • Interoperability among heterogeneous systems • Customer-oriented and supplier communication • Collaboration among all stakeholders • Remote and distributed design via Internet “online collaboration” • Design information/knowledge sharing among all collaborators • From concept to form • Direct constraint imposition • Multidisciplinary constraints • Scalable, flexible and efficient platform • Virtual product prototyping with Physical laws realization

13. Needs of Assembly Design in e-Design • Differentiation of assembly designs with different joints, such as weld joints and glue joints • Assembly design persistently capturing assembly/joining relations during design collaboration • Remote and transparent virtual simulation and testing to predict physical effects of joining in service-oriented architecture • Shared understanding of assembly design intent and implications during design collaboration

14. Mathematical Viewv Assembly Design (AsD) Model • Capturing assembly and joining information persistently for assembly design collaboration. • Consisted of Solid Model (SM) and Assembly Relation Model (ARM). • ARM can be transformed into three views • symbolic view, mathematical view, and graphical view. • All geometric entities in ARM are linked to a related SM. • For lean assembly design data exchange, the AsD model’s XML data can be generated. Graphical View ARM Symbolic View {GMAW | single fillet | [FF11 (E1), FF22 (E2)] | [welding_condition], [fixture_location]} {FF11 :P11; FF21 :P21; FF22 :P21; FF21FF22 | RC12 = 0; FF11 FF22; IDI12(2) = {1}, JMI12(12) = {1, 2}, JJI12(12) = {1}, JDI12(12) = {0}}

15. Lean Information Sharing Engine Exhaustion Case Clutch Bell Gasket Manifold Clutch Shoe Clutch Bearing Clutch Gear

16. Selective Lean Information Exchange in Assembly Design • To overcome the bandwidth limitations on Internet/Intranet • To achieve secured relationships among participants • To monitor design changes and variations • An AsD model captures persistently assembly engineering relations during this selective transition

17. e-Designer e-Designer e-Designer 3 SM 4 6 1 5 8 2 7 2 1 5 8 5 1 8 Vendor 2 e.g., Auto-supplier (Exhaust system) Vendor 1 e.g., Auto-supplier (Engine case) SM SM Assembly Design in e-Design Environment ARM/ Analysis Service Providers e.g., ANSYS System Integrator e.g., Auto-manufacturer (Automobile diesel engine) Pegasus Multi-Kernel Agent Pegasus Service Manager • CAD Model • CAD Kernel Model • CAD Model • CAD Kernel Model Index of processes #

18. Assembly Implication and Virtual Assembly Analysis (VAA) • Prediction of various effects corresponding to specified joining process in up-front design is very critical to understand the performance of assembly design • Transparent and remote virtual simulation and testing on joining • Natural collaboration of design tools and analysis tools • Equal understanding of assembly design implications during design collaboration • A set of joining process implications (i.e., riveting and arc welding) are developed as a framework. • A third party analysis tool, such as ANSYS, is used as the assembly analysis service provider • Assembly Implications • Physical effects • Spatial relationship implication • The assembly implication engine including VAA embedded into assembly design process, captures various implication information.

19. Load/B.C. Material Selection Joining Method Specification AsD Model Material Service Request Material Service Response Analysis Input Analysis Service Response Pegasus Service Manager Engineering Information Service Provider Analysis Service Provider Analysis Tools (ANSYS, ABAQUS, ADINA, CFX, etc.) Engineering Material Library VAA Tool VAA Tool AsAM Generation Load/B.C. Specification e-Designer Material Specification Solver Determination Analysis Response Interpretation AsD Engine Material Broker VAA Broker

20. Physical Realization Designer’s Intent Analysis Spatial Relationship Implication • Each S/R can be interpreted as a constraint imposed on the d.o.f. between relative mating or interacting features • Any allowable motion for parts has to follow a path along the directions specified by the d.o.f. in order to maintain their S/R. • The designed S/R are realized and maintained (or enforced) in the physical assembly by joining • In this manner, all collaborative design participants can have an equal understanding of design intent on assembly. Joint Design Space Inferred S/R Assembly Design Space Designed S/R Designed d.o.f. Implied d.o.f.

21. Assembly Design Decision (ADD) Problem • ADD problem: • When a problem on the current assembly design is indicated, a designer should make a decision whether to accept the current joint or modify it. If the joint should be modified, then should the current joining method be controlled or another joining method considered?

22. Assembly Design Decision Making (ADDM) • To propose AsD alternatives to the designer by considering AsD information, obtained from the AsD and AsI engines, and assembly/joining knowledge. • A hierarchical semantic net (HSN) model is introduced as a core model to represent evaluation knowledge and AsD knowledge, which is inevitable in knowledge based design decision making like ADDM. • Analytic Hierarchy Process (AHP) model • In general, the ADD problem is a multicriteria decision making problem. AHP is known as one of the well-received multicriteria evaluation methods. • However, since the ADD problem is in nature knowledge-intensive, the typical AHP model lacks knowledge representation power. • Hence, semantic net is employed to represent AsD and evaluation knowledge of AsD alternatives of the AHP model. • HSN model • The semantic net is embedded in the alternative, which is a component of the AHP model.

23. Hierarchical Semantic Net (HSN) Model • Unlike a typical AHP, the weights of criteria can be determined by external rule bases or users. • e.g., if the demand for the product is high, the cost criterion will have relatively low weight in comparison to other weights. • e.g., if the financial situation of the company is weak and the company is willing to reduce cost, then the cost criterion will have a high weight. • Rules can be built based upon domain experts’ knowledge. • Evaluation values of each design alternative are determined from inner knowledge of each criterion.

24. HSN and e-Design • Utilizes distributed decision analysis models and design evaluation knowledge in enterprise-wide and world-wide collaboration • To monitor and evaluate design changes and variations • The assembly design knowledge captured from design collaboration can be seamlessly transformed into an AHP-hierarchy (HSN) for ADDM. • Provide an environment that design collaborators can impose their constraints/specifications on the ADDM using AHP. • The ADDM can manage interactions between alternatives and also between criteria. • Allows independence between evaluation knowledge and design knowledge • The addition of new criterion or decision models will not affect the evaluation of design alternatives. It also enables the ADDM system to be scalable and extendable.

25. Assembly Design Alternative Internet Assembly Implication Assembly Design Model Assembly and Joint Design Assembly Implication Assembly Design Specification Assembly Components & Assembly Operation Internet Assembly Service Request Assembly Service Response Overall Architecture of AOT Assembly Operation Tools (AOT) Manufacturing Knowledge Base Assembly Advisory (AsA) Engine Geometric and Assembly Process Constraints Interaction Assembly/ Joining Knowledge Base ADDM Assembly Design (AsD) Engine Assembly Implication (AsI) Engine Assembly Graphic Interface Spatial Relationship Specification Spatial Relationship Implication (SRI) Tool Designer Assembly Feature Formation Virtual Assembly Analysis (VAA) Tool Engineering Relation Extraction Analysis Tools (ANSYS, ADINA, CFX, etc.)

26. Demonstration • Demonstrated using a case study: • The design of a base sub-assembly of an automotive space-frame. • This case study is based on given design specifications • i.e., maximum allowable stress and deformation • The developed VAA method can predict potential AsD problems and can provide design/engineering information to improve the current AsD (that does not meet the assembly specification).

27. Assembly Design of an Automotive Space-Frame Sub-Assembly • Recent emphasis on lightweight environmentally sound car design (Buchholz 1999) • An aluminum space frame assembly for an automobile • Made up of aluminum beams with rectangular sections

28. Spatial Relationship Specification Joining Method Specification S/R Implication Validation AsD Model Generation Product Data Sharing Assembly Design Processes

29. AsAM Generation VAA Request VAA Result Display VAA Processes

30. Assembly Problem Indication AsD Alternative Generation AHP Sensitivity Analysis ADDM Processes

31. Industry Benefits: AOT Capability vs. Existing Commercial CAD Systems

32. Conclusions • This presentation illustrates that the new DoD acquisition process can be realized by employing e-Design tools • System approach advocated in the new acquisition process guides the e-Design process • The system and technical views of the acquisition process map into the e-Design system architecture • The e-Design service-oriented architecture maps into the distributed GIG system

33. Sample Partners of the Center FEDERAL ACADEMIC INDUSTRIAL

34. Thank you! Questions?